Candace,
I cannot speak for RainCad so I am not familiar with its application. In searching online it appears to offer basic irrigation design items and elements. We have both AutoCad and Land FX with the Irrigation FX as well. Both operate well together or Land FX on its own. I think the total Land FX subscription is going to offer you a much superior product than what you are currently getting. It takes a little while to get up to speed (as does any software) but once you are acclimated you can start to tear through your construction or schematic plans. Their webinars are a great tool as is their online forum and the tech support is very good. The cost can seem steep up front but once your on subscription it is very affordable. If you do enough design work I would tell you that if you are not using land fx your wasting your money.